There are 4 different types of cells in 5G NR:
1. PCell
2. PSCell
3. SCell
4. SpCell
1. PCell:
-> Primary Cell
-> It will come under MCG.
-> There might be many cells under MSG.
-> PCell is used to initiate the initial access.
-> It is considered as main cell in MCG.
2. PSCell
-> Primary Secondary Cell
-> It will come under SCG.
-> PSCell performs the initial access under SCG.
3. SCell
-> Secondary Cell
-> It will come under MCG/SCG
-> UE might be configured with one or more SCell in connected mode.
-> SCell can be activated or deactivated according to traffic.
4. SpCell
-> Special Cell
-> SpCell = PCell + PSCell
Different types of Cell Groups:
1. MCG
2. SCG
1. MCG:
-> Master Cell Group
-> It is the group of serving cell having a PCell and optionally one or more SCell.
2. SCG:
-> Secondary Cell Group
-> SpCell = PCell + PSCell
Different types of nodes
There are 2 different nodes in 5G NR
Master Node: This node provides the control plane connection to the core network in case of multi radio dual connectivity (MR-DC).
Secondary Node: This node will not have control plane connection to the core network. It provides additional resources to the UE in case or MR-DC.